The Conventicle Act of 1664, 16 Charles II c. 4, was an English statute that forbade religious assemblies of more than five people outside the auspices of the Church of England. This law was part of the programme of Edward Hyde, 1st Earl of Clarendon, to discourage nonconformism and to strengthen the position of the Established Church.

Other statutes that were part of Clarendon's programme include:

the Five Mile Act, 17 Charles II c. 2, (1665), which sought to prevent nonconformists from living in incorporated and chartered towns.

The operation of these laws at least as far as Protestants were concerned was mitigated somewhat by Charles II's Royal Declaration of Indulgence in (1672), which suspended the execution of penal laws and allowed a certain number of non-conformist chapels to be staffed and constructed, with the pastors subject to royal approval.

The Conventicle Act and Five Mile Act were repealed in 1689.

(The '16 Charles II c. 2' nomenclature is reference to the statute book of the numbered year of the reign of the named King in the stated chapter. This is the method used for Acts of Parliament from before 1962.